Uninformed individuals promote democratic consensus in animal groups

Conflicting interests among group members are common when making collective decisions,
yet failure to achieve consensus can be costly. Under these circumstances individuals may be
susceptible to manipulation by a strongly opinionated, or extremist, minority. It has previously
been argued, for humans and animals, that social groups containing individuals who are uninformed,
or exhibit weak preferences, are particularly vulnerable to such manipulative agents. Here, we
use theory and experiment to demonstrate that, for a wide range of conditions, a strongly
opinionated minority can dictate group choice, but the presence of uninformed individuals
spontaneously inhibits this process, returning control to the numerical majority. Our results
emphasize the role of uninformed individuals in achieving democratic consensus amid internal
group conflict and informational constraints.